This application claims the benefit of Japanese Patent Application No. 2000-265521, filed Sep. 1, 2000 in Japan, which is hereby incorporated by reference for all purposes as if fully set forth herein.
1. Field of the Invention
This invention relates to chemical vapor deposition methods, and more particularly, to materials used in chemical vapor deposition methods as well as films and device elements fabricated using the chemical vapor deposition method.
2. Discussion of the Related Art
Chemical vapor deposition (CVD) is a widely used method to mass-produce metal type films. Materials used in CVD include, for example, silane, arsine, diborane and ammonia, which are gases at room temperature, or is limited to liquids such as tetraetokissilane (TEOS) or trimethylgalium (TMG), which can easily be vaporized.
Recently, the excellent performance of CVD has been recognized and used in many different areas. It has been researched extensively, especially in the semiconductor field. Materials such as transition metal compounds and alkali metal compounds, which have not previously been considered candidate material for use in CVD, are now proposed.
However, the above mentioned transition metal compounds and alkali metal compounds do not have associated organic metals (such as alkyl metals similar to trimethylaluminum) with appropriate vapor pressure. Thus, the use of associated metal complexes, especially the xcex2-diketone complex, has been proposed for use as a material for CVD.
The proposed metal complexes include for example, DPM2Ca, DPM2Sr, DPM2Ba, DPM2Ca:triene, DPM2Sr:teranene, DPM2Ba:teraene, DPM2Pb:triene, DPM3Ru:triene, DPM3Ru:tetraene, DPM2Pb, DPM2 (i-OPr)2 Ti, DPM3Ru, Hfac2Pt, HfacCu:TMVS, HfacCu:ATMS, HfacCu:BTMSA, DPM4Zr, DPM4Hf, DPM3La, DPM3Bi.
However, there are problems with these CVD materials.
For example, the useful temperature range to form metal films by thermal decomposition of the material near the substrate where the film is to be formed is very narrow.
In addition, low temperature film formation is often required in the manufacture of components that contain semiconductors. When the decomposition temperature is high, the CVD material decomposes at a location far from the substrate on which the film must be formed. Since the reaction does not occur at the substrate surface, the film surface uniformity is then reduced. For example, when a film is deposited on a rough surface with bumps and dips, it may not coat the bottoms of the superficial indentations when the decomposition temperature is high. Even if the film forms, it may not be uniform and may be bumpy. In current semiconductor processes, a design rule of below 0.5 microns is becoming a standard, and it is often difficult or impossible to deposit films that meet this standard when the decomposition temperature is high.
On the other hand, these CVD materials often do not decompose efficiently at low temperatures, so low temperature processes often cannot achieve the required film properties.
Accordingly, the present invention is directed to a chemical vapor deposition (CVD) method and related materials that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An advantage of the present invention is a film fabrication technology that allows the formation of high quality films using CVD of a metal xcex2-diketonate complex.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the scheme particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a process for chemical vapor deposition comprises depositing a film using a metal xcex2-diketonate complex and an xcex1, xcex2-unsaturated alcohol.
In another aspect, the present invention includes a process for chemical vapor deposition for forming a film on a substrate comprising contacting a metal xcex2-diketonate complex and an xcex1, xcex2-unsaturated alcohol at the same time, at different times or alternately on the substrate.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.